If you can swing the time and get into an affordable program, I'd go for the four year for a few reasons.
-In my area (NYC/NJ area) most major hospital systems don't hire associate degree nurses anymore. And they want their current nurses with 2 year degrees to go back for their BSN. Given that even most community hospitals have been bought out by big names in my area, you won't be get into acute care with a 2 year now in my area.
-Rehab, primary, and nursing homes around me hire associates. Pay is substantially less compared to acute care in my area (usually at least 8 to 10 dollars an area).
-Programs in my area advertise as 2 year, but don't include the basic requirements in its schedule. So for most people I know who took 2 year programs, they ended up in school for the 3 to 4 year run to finish the requirements then the nursing program itself.
-If you end up moving to management, you will need at least a BSN if not a masters. You can eventually get there with a 2 year, but the road will be much longer.